New member/first post.
I just wanted to relay my experience with aftermarket thermostats.
I just bought a high-mile I30 that was advertised as needing a new engine because of a hole in the radiator and an overheat. Checking it out, the engine ran fine and didn't make any funny noises, so I bought it figuring that I would probably have to do the head gaskets. No problem, I'm pretty experienced at that. In my order to RockAuto for a new radiator and water pump (weep hole leaking), I decide that I will really be proactive and buy a new thermostat at the same time. Having read horror stories about aftermarket thermostats, I sprung a few sheckles more for a name brand thermostat, a Beck-Arnley, made in Germany.
Turns out, didn't have to do the head gaskets either. Big win. Water pump, thermostat, and radiator replaced. Coolant filled and properly purged. Driving the car revealed that the temperature on the gauge would fluctuate, especially on acceleration. Nothing close to an overheat, but a higher drift when a load was placed on the engine or a/c turned on. In my world, coolant gauge temp should be steady unless you are pulling a cattle trailer up a mountain pass in August.
Long story shorter, I reinstalled the original OEM thermostat and temperature is rock-steady. There really is a difference between OEM and the rest. Examination of the two reveal two differences that I think might cause a difference in performance. OEM thermostat has a metal shield that extends down around the bottom that obviously is there to direct or shield against flow. None of the aftermarket thermostats that I've seen has this. Also, the OEM has a jiggler pin which may greatly facilitate system purge of air. Beck-Arnley did not have this.
Hopefully, this post may save someone a little time and a lot a head scratching. OEM thermostat is the way to go.
I just wanted to relay my experience with aftermarket thermostats.
I just bought a high-mile I30 that was advertised as needing a new engine because of a hole in the radiator and an overheat. Checking it out, the engine ran fine and didn't make any funny noises, so I bought it figuring that I would probably have to do the head gaskets. No problem, I'm pretty experienced at that. In my order to RockAuto for a new radiator and water pump (weep hole leaking), I decide that I will really be proactive and buy a new thermostat at the same time. Having read horror stories about aftermarket thermostats, I sprung a few sheckles more for a name brand thermostat, a Beck-Arnley, made in Germany.
Turns out, didn't have to do the head gaskets either. Big win. Water pump, thermostat, and radiator replaced. Coolant filled and properly purged. Driving the car revealed that the temperature on the gauge would fluctuate, especially on acceleration. Nothing close to an overheat, but a higher drift when a load was placed on the engine or a/c turned on. In my world, coolant gauge temp should be steady unless you are pulling a cattle trailer up a mountain pass in August.
Long story shorter, I reinstalled the original OEM thermostat and temperature is rock-steady. There really is a difference between OEM and the rest. Examination of the two reveal two differences that I think might cause a difference in performance. OEM thermostat has a metal shield that extends down around the bottom that obviously is there to direct or shield against flow. None of the aftermarket thermostats that I've seen has this. Also, the OEM has a jiggler pin which may greatly facilitate system purge of air. Beck-Arnley did not have this.
Hopefully, this post may save someone a little time and a lot a head scratching. OEM thermostat is the way to go.
Senior Member
Glad you figured it out, and welcome to the org. 
Thermostats are definitely an OEM only replacement.
Thermostats are definitely an OEM only replacement.
Beck-Arnley from RockAuto is $17.13
OEM from Courtesy Nissan is $15.80
OEM from Courtesy Nissan is $15.80
Darn it. I thought I was being original!
Or, it could be that great minds think alike?
Either way, I like it. Thanks for posting it!
Or, it could be that great minds think alike?
Either way, I like it. Thanks for posting it!